(19)

(11)

EP 0 256 076 A1

(12)

(43) Date of publication: 24.02.1988 Bulletin 1988/08 (21) Application number: 87901078.0 (22) Date of filing: 30.01.1987

(51) International Patent Classification (IPC):  H03D 1/ 22( . ) H03M 1/ 20( . ) H03D 3/ 00( . ) H03M 1/ 12( . ) (86) International application number: PCT/GB1987/000068 (87) International publication number: WO 1987/004880 (13.08.1987 Gazette 1987/18)

(84) Designated Contracting States: AT BE CH DE FR GB IT LI LU NL SE (30) Priority: 30.01.1986 GB 19860002227 30.01.1986 GB 19860002230 (71) Applicant: PLESSEY OVERSEAS LIMITED Ilford Essex IG1 4AQ (GB)	(72) Inventor: SAUL, Peter, Henry Northants NN12 7JB (GB) (74) Representative: Field, Howard John, et al  THE PLESSEY COMPANY plc Intellectual Property Department Vicarage Lane Ilford Essex IG1 4AQ Ilford Essex IG1 4AQ (GB)